045
FXUS66 KMTR 191136
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
436 AM PDT Thu Sep 19 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 239 AM PDT Thu Sep 19 2024

There is a slight chance of showers and even a couple rumbles of
thunder over southern Monterey County later this afternoon and
early evening, with the best chances farther inland you go into
higher elevations. Locations under the influence of the marine
layer along the coast will be in the 60s and low 70s. Interior
locations away from the marine layer will be in the 70s to low
80s. A warming trend for this weekend into the beginning of next
week remains on track.

&&

.SHORT TERM...
(Today and tonight)
Issued at 239 AM PDT Thu Sep 19 2024

A positively tilted upper level low currently situated offshore in
the vicinity of Big Sur will continue to track south along the
California coastline toward Los Angeles today and eventually begin
to move inland over San Diego by tomorrow afternoon and evening. The
best chance for showers and/or thunderstorms will be farther inland
where orographic upslope flow enhances an otherwise weak
thermodynamic environment for convection. Highs today will
generally be 5-10 degrees below normal, and slightly warmer
tomorrow.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 239 AM PDT Thu Sep 19 2024

The upper level trough moving across our area today and tomorrow
will eventually shift inland over SOCAL by tomorrow evening.
Increasing H50 heights and thickness values over the weekend will
result in temperatures rebounding back up above normal by the end of
the weekend into the beginning of next week. A weak upper level
disturbance interrupts the ridging pattern off the coast of central
California by late Sunday into early Monday morning, while the
northern extent of the ridging amplifies over the Pacific Northwest.
The net result is warmer than normal temperatures and increasing
heat risk concerns the farther inland and north you go for the
beginning of next week. The warming trend may result in the need for
a heat advisory for those locations as soon as Sunday, but more
likely Monday and Tuesday.

&&

.AVIATION...
(12Z TAFS)
Issued at 421 AM PDT Thu Sep 19 2024

Low CIGs build through the night last into the mid to late
morning with some light rain lingering around the Monterey Bay and
Central Coast. Pockets of drizzle and mist will affect the coast
as well as the Monterey Bay and STS. Winds stay light to moderate
through the morning. Widespread VFR returns for the TAF sites into
Thursday afternoon, but status lingers on the immediate coast.
Expect moderate winds to build into the afternoon and linger into
the evening. Coastal cloud cover moves inland slightly early
Thursday evening, affecting both bays with IFR CIGS becoming
widespread later that night.

Vicinity of SFO...IFR CIGs build into the late night and last
into the late morning with light to moderate winds. Winds increase
into and become moderate in the mid afternoon. Winds will reduce
slightly into Thursday evening and MVFR CIGs return in the late
evening and early night.


SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Lingering showers along with MVFR/IFR CIGs
last through most of the thing. CIGs lower into early Thursday with
mist and drizzle affecting the area. CIGs scatter and winds become
more moderate into Thursday afternoon. IFR CIGs return  Thursdsay
evening as winds reduce.

&&

.MARINE...
(Today through Tuesday)
Issued at 421 AM PDT Thu Sep 19 2024

Northwesterly winds increase and seas will become rougher in the
outer waters through the day. Winds and seas remain elevated
through the weekend but ease into the next work week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 3 AM PDT
     Saturday for Pt Arena to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...JM
LONG TERM....JM
AVIATION...Murdock
MARINE...Murdock

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